保温车也称冷藏车，是一种运输对温度有较高要求的货物的铁路货车，常用来运输新鲜食物，如鱼、肉、鲜果、蔬菜等。

大陆

中国铁路货车基本型号用“B”表示保温车。

**使用「R」代表冷藏车。

A refrigerator car (or "reefer") is a refrigerated boxcar (U.S.), a piece of railroad rolling stock designed to carry perishable freight at specific temperatures. Refrigerator cars differ from simple insulated boxcars and ventilated boxcars (commonly used for transporting fruit), neither of which are fitted with cooling apparatus. Reefers can be ice-cooled, come equipped with any one of a variety of mechanical refrigeration systems, or utilize carbon dioxide (either as dry ice, or in liquid form) as a cooling agent. Milk cars (and other types of "express" reefers) may or may not include a cooling system, but are equipped with high-speed trucks and other modifications that allow them to travel with passenger trains.